• Journal of the Korean Data and Information Science Society
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• v.22 no.3
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• pp.413-421
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• 2011

The present study was carried out to summarize the effect of garlic in the hyperlipidemia rats by meta-analysis related studies. The association measure to test effect of garlic was the mean difference (MD). In this particular fixed-effect model of mean difference, body weight, liver weight, kidney weight and heart weight were significantly decreased (p < 0.05). Also, blood glucose, plasma total cholesterol, plasma triglycerides, LDL-cholesterol, liver cholesterol, liver triglycerides were significantly decreased. HDL-cholesterol was significantly increased. In this case of heterogeneous variable, random effect model was applied. In this model, liver weight, blood glucose, plasma total cholesterol, plasma triglycerides, LDL-cholesterol, liver cholesterol, liver triglycerides were significantly decreased. HDL-cholesterol was significantly increased. According to the meta-regression analysis, duration of injection was significantly for kidney weight, testis weight, plasma total cholesterol, plasma triglycerides, HDL-cholesterol, LDLcholesterol, liver cholesterol, liver triglycerides.

• Journal of Korean Tunnelling and Underground Space Association
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• v.5 no.3
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• pp.217-226
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• 2003

This study is focused on the finding out load transfer mechanism in the ground near the tunnel during tunnel excavation in the jointed sandy ground. Laboratory model tests were performed on various cases of the overburden heights above tunnel crown, location, and degree of discontinuity planes. For model tests, a movable plate was installed in the midst of the bottom of sandy ground. This plate, moving downwards, was intended to model the stress relaxation during tunnel excavation. The load transfer was measured at the fixed separated bottom plates adjacent to the movable plate. As the result, the loosening zone and the load-transfer form around the tunnelling site were affected by the overburden height and the characteristics of discontinuous planes. And large loosening zone was developed along the discontinuous planes which were close to the tunnel.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.2
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• pp.277-286
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• 1989

Turbulent flows around two-dimensional vehicle-like bodies in ground proximity are numerically simulated. The Reynolds averaged Navier-Stokes equations with a k-.epsilon. turbulence model are numercally solved, and a body-fitted coordinate system is used. It is shown that the simulation is acceptable in comparison with limitted data measured in the wind-tunnel. According to numerical simulations, drag coefficients are under-estimated and lift coefficients are over-estimated during the model test in the wind-tunnel if the ground is fixed. Such ground effects are reduced as Reynolds number is increased. Reducing the gap between the vehicle and the ground make drag coefficients smaller and lift coefficients larger. The changes in static pressure distributions on the bottom and the rear surface play dominent roles in determination of the drag and the lift of the body in ground proximity. Drag component less than 10% of the total amount is contributed by skin-frictions. When the slant-angle of the body is reduced, the drag shows its minimum value and the lift shows its maximum value at about 22 degree.

• The Journal of Fisheries Business Administration
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• v.44 no.2
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• pp.19-33
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• 2013

China is the world's largest producer of aquatic products and its fishery sector is comprised primarily of aquaculture facilities, both fresh and seawater, and a much smaller wild catch component. The expansion of the aquaculture sector continues to boost China's aquatic output. The increase is attributable to several factors. Among them rapidly growing domestic demand is no doubt one of the most important reasons. Rapid economic growth and rising disposable income are influencing domestic consumption and the economic recovery of major import markets is further stimulating consumption of China's aquatic products. This paper tries to examine the status, trend and reasons of consumption of aquatic products in China. Based on the analysis on the consumption of aquatic products and its change, this paper utilizes panel regression model to estimate the affecting factors of aquatic products consumption in China. By using panel data between 1997 and 2010, the results indicate that income, urbanization, aging and dummy variable have positive effects and fish price index has negative effect on China's aquatic products consumption as predicted. However, effects of meat consumption and education on fishery consumption are totally opposite with our predictions. In other words, it turns out that meat consumption has positive effect on fish consumption while education turns out to have negative effect. Finally the member of household does not show any significant effect on consumption of aquatic products in China.

• Journal of Forest and Environmental Science
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• v.32 no.3
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• pp.280-290
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• 2016

Stem diameter variability is an essential inventory result that provides useful information in forest management decisions. Little has been done to explore the modelling potentials of standard deviation (SDD) and coefficient of variation (CVD) of diameter at breast height (dbh). This study, therefore, was aimed at developing and testing models for predicting SDD and CVD in stands of Pinus caribaea Morelet (pine) in south west Nigeria. Sixty temporary sample plots of size $20m{\times}20m$, ranging between 15 and 37 years were sampled, covering the entire range of pine in south west Nigeria. The dbh (cm), total and merchantable heights (m), number of stems and age of trees were measured within each plot. Basal area ($m^2$), site index (m), relative spacing and percentile positions of dbh at $24^{th}$, $63^{rd}$, $76^{th}$ and $93^{rd}$ (i.e. $P_{24}$, $P_{63}$, $P_{76}$ and $P_{93}$) were computed from measured variables for each plot. Linear mixed model (LMM) was used to test the effects of locations (fixed) and plots (random). Six candidate models (3 for SDD and 3 for CVD), using three categories of explanatory variables (i.e. (i) only stand size measures, (ii) distribution measures, and (iii) combination of i and ii). The best model was chosen based on smaller relative standard error (RSE), prediction residual sum of squares (PRESS), corrected Akaike Information Criterion ($AIC_c$) and larger coefficient of determination ($R^2$). The results of the LMM indicated that location and plot effects were not significant. The CVD and SDD models having only measures of percentiles (i.e. $P_{24}$ and $P_{93}$) as predictors produced better predictions than others. However, CVD model produced the overall best predictions, because of the lower RSE and stability in measuring variability across different stand developments. The results demonstrate the potentials of CVD in modelling stem diameter variability in relationship with percentiles variables.

• Journal of the Korean Data and Information Science Society
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• v.23 no.4
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• pp.649-656
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• 2012

The present study was carried out to summarize the effect of caffeine in the lipid metabolic by meta-analysis. The association measure to test effect of caffeine was the Hedges's standardized mean difference (HG). In this particular fixed-effect model of Hedges's standardized mean difference, weight gain, heart weight, serum total lipid, serum triglycerides and liver triglycerides were significantly decreased (p < 0.05). Also, serum HDL cholesterol and serum LDL cholesterol were significantly increased. In this case of heterogeneous variable, random effect model was applied. In this model, weight gain, heart weight, serum total lipid, serum triglycerides, serum LDL cholesterol and liver triglycerides were significantly decreased in caffeine treated group. Also HDL-cholesterol was significantly increased in caffeine treated group.

• Environmental and Resource Economics Review
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• v.28 no.3
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• pp.415-435
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• 2019

The purpose of this study is to analyze the returns to scale by estimating the bigeye tuna production function of Korean distant longline fisheries in WCFPC waters. In the analysis, number of crews, vessel tonnage, number of hooks, and bigeye tuna biomass are used as input variables and the catch amount of bigeye tuna is used as an output variable in the Cobb-Douglas production function. Prior to the function estimation, the biomass of bigeye tuna was estimated by the Bayesian state-space model. Results showed that the fixed effect model was selected based on the hausman test, and vessel tonnage, hooks, and biomass would have direct effects on the catch amount. In addition, it was shown that the bigeye tuna distant longline fisheries in WCFPC water would have increasing returns to scale.

• Journal of the Korean Geotechnical Society
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• v.39 no.11
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• pp.33-40
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• 2023

This study explores the performance of pile foundations in highly expansive soil, incorporating magnesium oxide-based refractory materials. A controlled model chamber, housing a fixed pile, was utilized to induce ground expansion through fused magnesia (FM). The investigation focused on measuring the vertical displacement of FM-sand mixtures and the axial load on the pile in relation to depth and time. The study varied the amount of FM content (FM_c) at 30%, 50%, and 70%. The upward movement exhibited an augmentation with increasing FM_c, tapering off with depth as accumulation progressed toward the mixture surface. Compression and tensile forces were both evident along the pile for FM_c at 30% and 50%, while only a tensile force was observed at an FM_c of 70%. These results offer valuable insights for the analysis of pile behavior within FM-sand mixtures.

• The Journal of Engineering Geology
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• v.3 no.2
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• pp.149-165
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• 1993

Nowadays, the field hydraulic test is still an only method to evaluate groundwater characteristics in subsurface. The results of hydraulic test are very important for the concept model of fracture hydrogeology as well as the geometric pattern of fractures. The hydraulic tests performed in Korea are generally analysed under such assumption as steady radial flow in homogeneous aquifer or along simple geometry of fractures. Also the transmissivity measured in a fixed interval length is equivalent to a sum of individual fracture transmissivities in test legth. The boundary effects of weH hydraulics and the geometry of flow paths are hardly obtained from the test results analysed by a steady flow method. To circumvent this problem, the flow dimensional analysis was attempted from the results of constant pressure injection test carried out in a fractured granite area. A comparison of the hydraulic conductivity values from the transient and steady analysis shows that the latter is about a factor of 2~3 higher than the former. However, it was possible to analyse a flow dimension of each test interval from flow rate variation with time. The upper part of the bedrock(<10m deep) indicates an open boundary and the flow dimension shows nearly steady states, while the lower part of the bedrock(>25m deep) is characterized as sublinear flow dimension with a dosed boundary. In one of the test sections(15m deep), the flow dimension was changed from linear flow to spherical flow. From the experience of this study, one of the immediate problems to be solved is to enhance the field testing equipments, i.e., an accurate flowmeter with autorecording and a pressure detecting device to be able to install in the test section.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.2
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• pp.217-225
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• 2007

This paper proposes the real-time hybrid shaking table testing methods to simulate the dynamic behavior of a soil-structure interaction system with dynamic soil stiffness by using only a structure model as the physical specimen and verifies their effectiveness for experimental implementation. Experimental methodologies proposed in this paper adopt such a way that absolute accelerations measured from the superstructure and shaking table are feedback to the shaking table controller, and then the shaking table is driven by the calculated motion of the absolute acceleration (acceleration feedback method) or the absolute velocity (velocity feedback method) of foundation that is required to simulate the dynamic behavior of a whole soil-structure interaction system. The shaking table test is implemented by reflecting the dynamic soil stiffness, which are differently approximated from the theoretical one depending on the feedback methods, on the shaking table controller to calculate soil part. The effectiveness of the proposed experimental methods is verified by comparing the response measured from the test on a foundation-fixed structural model and that obtained from the experiment of a soil-interaction system under the consideration in this paper and by matching the dynamic soil stiffness reflected on the shaking table controller with that identified using the experimentally measured data.